Rotary engine



(Hommel.) 2 sheets-sheet 1.

- w. SMITH.

f ROTARY ENGINE; No. 536,160. 3 Patented Mar. 19, 1895.

(N'oModel.) 2 sneensgsheet 2,

wf SMITH. ROTARY ENGINE.

No. 536,160. PatentedMar. 19, 1895.

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y v UNITED STATES PATENT OEEICE,

WILLIAM SMITH, or CLARINDA, row-A.

ROTARY ENGINE.

SPECIFICATION forming part -of Letters Patent N0. 536,160, dated March 19, 1895.

Application tiled May 8, 1894. Serial No. 510,527. (No model.) i

To a/ZZ whom it may concern:

` Be it known that I, WILLIAM SMITH, of Clarinda, in the county of Page and State of Iowa, have invented certain new and useful Improvements in Rotary Engines; and I do hereby declare that the following is a full, clear,

' and exact description thereof, reference being had to the accompanying drawings, and to the letters of reference markedv thereon, which steam consumption. f

To this end the invention consists in the matter hereinafter set forth and particularly pointed out in the appended claims.

A principal feature of my invention consists in revolubly mounting the smooth wheel which acts as a rotaryT piston within the cylinder, upon a crank formed on the driving shaft, 'so that under the pressure of the steam said wheel will roll around the inner surface of the cylinder and act upon the crank in the same manner as the piston of an ordinary reciprocating engine.

AY further feature of my improvement consists in operating the sliding abutment which rests constantly upon the rotary piston and separates the steam space of the cylinder from the exhaust space thereof, by means of radial links pivotally connecting said abutment with the crank pin upon which the revoluble piston is mounted.

A third feature of my invention consists in providing a cut off valve operated by the sliding abutment plate by means of which the quantity of steam admitted at each revolution of the engine may be varied as desired without regard to the proportions of the cylinder and piston.`

In the accompanying drawings: Figure 1 is a sectional elevation of a rotary engine constructed in accordance with my invention. Fig. 2 is a partial section taken on line 2-2 of Fig. 1. Fig. 3 is a sectional elevation taken on line 3-3 rof Fig. 1.

A designates the engine cylinder which' is mounted upon a suitable base A', and is in this instance cast integral therewith.

B is the main driving shaft of the engine and extends into the cylinderA through cen- `tral stuffing boxes a in the heads A2 thereof,

said shaft being revolubly mounted within suitable bearings a. supported upon standards A3 which` are bolted to the base A. Within the cylinder A the shaft B is formed with a crank B upon the crank pin B2 of which a smooth cylindric wheel C, which forms the rotary piston, is revolubly mounted so as to bring its periphery in rolling contact with the inner cylindric surface of said cylinder A. Fo-r the purpose of enabling the contact between the cylindric surfaces of the cylinder A and wheel C to be adjusted as desired and to provide for the taking up of any wear which may occur between them, the end portions b of vthe crank pin B2 are made to revolubly engage suitable apertures in the arms b of the crank and are adjustably secured therein by means of set screws b2, the central portion bsof the crank pin, upon which the smooth wheel C is mounted, being at the same time formed eccentric to the end portions b which engage the crank arms b. With this construction it will be obvious that by revolubly adjusting thecrank pin in the crank arms b the wheel C may be carried toward or away from the inner surface of the cylinder as may be desired.

D designates a sliding abutment plate or plunger projecting into the cylinder from a steam chest A4 provided on the top thereof,

said plate being closely fitted to reciprocate i within a suitable vertical recess a2 provided in said steam chest. Said plate, in my improved construction,is maintained in constant contact with the periphery of the piston wheel C by means of radial links E, the inner ends of which are sleeved upon the central portion b3 of the crank pin B2 on either side of the hub c of the wheel, and between said hub and the crank arms b'. Said arms b extend upwardly on either side of the central web o' of the wheel and have their upper ends e bent outwardly to pivotally engage lateral arms or lugs d provided on the sides of the block D vand projecting inward past the edges of the rim o2 of the wheel. Said arms d are in this instance formed by the lower ends of sepa-.

rate strips D which are secured to the side edges of the plate D by suitable screws d2 orl within a recess d3 in the blockD and is maintained under yielding pressure by springs d4 in the upper portion of the recess D2. Said inner block D2, which is similar to that set forth in my previous patent, No. 517,986, dated April 10, 1893, obviously acts asa packing to compensate for any wear which may occur between the lower face of the block D and the periphery of the wheel C and to maintain a practically steam tight joint between the plate and wheel at all times.

Suitable steam and exhaust ports a, preferably made exactly similar in shape, are provided on either side of the abutment plate D. At their outer ends said ports are adapted to receive pipes F which, as herein shown, are provided with three way valves F which serve to connect each of the pipes F with both steam and exhaust pipes G and H respectively. The valves F are designed to be simultaneously operated by levers f which are pivotally connected by a link f', in such man ner that when the handle of one valve is moved so as to throw the adjacent pipe F in communication with the steam pipe G the handle of the other valve will be so moved as to throw the other pipe F in communication with the exhaust pipe. H, and vice versa. Obviously with this construction the engine is adapted to rotate in either direction and inay be reversed at any time by shifting the handles f. The reversing mechanism described forms no part of my present invention and has been fully set forth in connection with my previous patent, No. 517,985, dated April 10, 1893, hereinbefore referred to.

As a further and distinct improvement and for the purpose of enabling the admission of steam to be cut ott at any part stroke instead of being admitted throughout substantially the entire revolution of the piston, as in my previous engines, I have in this instance shown a cylindrical valve chest A5 mounted upon the top of the steam chest A4 and have supply pipe J opening into the top thereof,

except at such times as the valve I by its upward movement acts to cover said openings a7 and. thus cut off the steam supply to the pipes G. The parts are so proportioned that the downward movement of the valve l begins to uncover the openings a7 as soon as the plunger l begins to descend after the piston C has passed its uppermost position. Steam will therefore begin to flow at this point through that one of the pipes G between which and the cylinder communication has been established through the three way valves F', and will continue to iiow until the valve I has reached its lowermost position and risen again far enough to close the openings a7. By such closing of the openings a7 the steam will obviously be cut off and will cease to 'low until said openings are again uncovered by the downward movement' of the valve piston. Such point of cut off is in this instance provided at about three fourths of the stroke. Obviously, however, although the three fourths cut off arranged for in this instance is deemed desirable for many purposes, the parts lnay be readily so proportioned as to provide an earlier or a later cut oit it' so desired. It will further be obvious that in cases where it is desired to have the engine rotate in one direction only, one of the steam pipes G and the opposite exhaust pipe Il together with the three way valve connections shown may be entirely dispensed with, the remaining steam pipe G being left in communication with the port c4 on one side of the abutment and the remaining exhaust pipe with the port a4 on the other side of the said abutment.

In the operation of the engine thus described the steam admitted at one side of the abutment plate D will obviously exert a direct pressure on the periphery of the wheel C which will at once be transmitted to the crank pin and tend to rotate the crank shaft in substantially the same manner as in a reciprocating engine, with the obvious additional advantage that such rotary impulse on the crank pin, instead of being interrupted twice in each revolution by dead center points, is interrupted at only one point which will occur as the piston wheel C reaches its uppermost position. Furthermore, it will be obvious that the rolling contact between the inner surface of the cylinder and the periphery of the piston wheel C will offer almost no resistance to 'the rotation of the engine, so that the engine is not only very effective in its application of power, but involves the loss of very little of the power generated, in the friction of moving parts. As soon as the steam is out off by the piston valve I expansion occurs in the cylinder A in the same manner as in a reciprocating engine, and as hereinbefore stated such expansion may be carried on to any desired degree by the proper arrangement of the cut oit gear.

I claim as my invention- 1. In a rotary engine the combination with the steam cylinder of a concentricaily mount- ICO IIO

ed driving shaft provided with a crank within the cylinder, a smooth cylindric wheel revolubly mounted on said crank with its periphery in rolling contact with the interior of the cylinder, a reciprocatory abutment plate means p for positively maintaining said plate constantly in contact with the surface of said Wheel, and steam and exhaust ports on opposite sides of said plate, substantially as described. f

2. In a rotary engine the combination with the steam lcylinder of a concentric driving shaft provided with a crank within the cylinder, the pin of said crank being made with eccentric end portions adjustably engaging apertures in the crank arms, a smooth cylindric wheel revolubly mounted on said crank pinwith its periphery adjustably engaging the inner surface of the cylinderfand in rolling contact therewith, a reciprocatory abutment plate constantly4 engaging the surface of said wheel, and inlet and exhaust ports on opposites of said plate, substantially as described.

3. In a rotary engine the combination with the steam cylinder of a concentric driving shaft provided with a crank within the cylinder, a smooth cylindric wheel revolubly mounted on the crank pin with its periphery in rolling contact with the inner surface of the cylinder, a reciprocatory abutment plate, and radial arms pivotally connecting the abutment plate with the crank pin to maintain the ,plate in constant contact with the surface of the wheel, substantially as described.

4. In a rotary engine the combination with the steam cylinder of a concentric shaft provided with a crank within the cylinder, a smooth cylindric wheel revolubly mounted on said crank with its periphery in rolling contact with the inner surface of the cylinder, a reciprocatory abutment plate constantly engaging the surface of said wheel, a steam chest within which said abutment plate reciprocates, steam and exhaust ports on opposite sides of said abutment plate, a valve chest mounted on said steam chest and provided with a valve connected with the abutment plate to reciprocate therewith, a steam pipe leading from said valve chest to the steam port and adapted to be closed (on its upper end by said valve piston during a portion of the stroke thereof and a steam supply pipe opening into said valve chest and communicating with said steam pipe when the latter is uncovered by the valve piston, substantially as described. A

In testimony that I claim the foregoing as my invention I affix my signature in presence of two witnesses.

WILLIAM SMITH. Witnesses:

TAYLOR E. BROWN, WALTER A. BURNET. 

